A glucagon test measures the amount of a hormone called glucagon in your blood. Glucagon is produced by cells in the pancreas. It helps control blood sugar levels.
How the test is performed
Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.
Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.
A specific laboratory technique called radioimmunoassay (RIA) is used to check for the hormone glucagon in the blood.
How to prepare for the test
Your health care provider will tell you if you need to fast for a period of time before the test.
How the test will feel
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed
Glucagon stimulates the liver to release glucose. As the level of blood sugar decreases, the pancreas releases more glucagon, and vice versa.
Your health care provider may measure your glucagon levels if you show symptoms of:
In a rare syndrome, a tumor in the pancreas called a glucagonoma can produce excess glucagon and cause diabetes.
People with insulin resistance or type 2 diabetes often produce very high levels of glucagon.
What the risks are
Veins vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Fainting or feeling light-headed
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
Ari S. Eckman, MD, Chief, Division of Endocrinology, Diabetes and Metabolism, Trinitas Regional Medical Center, Elizabeth, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.